Most black and tri-color ink-jet printers have two pens on the printhead carriage, one black with a given number of vertically arranged orifices and one tri-color with the same number of vertically arranged orifices evenly distributed among the three primitive colors, i.e. cyan, magenta and yellow. Because of the disparate numbers of orifices between a given color and black, and because in order to maximize throughput substantially all of the orifices of both typically are used to deposit ink during each pass of the printhead carriage, color (tint) variations appear as regular-periodic, horizontal bands in areas where color and black ink are adjacent and/or touching, e.g. when printing a dark cyan tint by interposing black dots within an otherwise cyan field. This visible "color-banding" phenomenon--which is caused by varying time delays between interposed, color and black liquid ink dot deposition--previously has been addressed at significant throughput cost, and with only limited success.
One such conventional solution will be referred to herein as "shingling." Shingling is a method of printing whereby a first checkerboard print pattern of dot groups resembling shingles on the roof of a house first are printed during a first pass of the printhead and subsequently interstitial dot groups within one or more complementary checkerboard print patterns are printed during one or more further passes over the same print area. The overhead cost of shingling in the best case wherein two interposed checkerboard patterns are used approaches 100%, thus typically reducing high-quality color printing throughput by almost 50%.